Bloomberg — Fine wrinkles that emerge with age tend to appear earlier and to be more severe in cigarette smokers, a study found.The extra creases represent smoking-related skin damage and aren’t confined to areas regularly exposed to the sun, researchers at the University of Michigan in Ann Arbor said today.

To assess the affect of smoking on sun-protected skin, the scientists used photographs of the right underarms of 82 people aged 22 to 91.

Scientists are studying smoking-related diseases to improve treatments and gather evidence that may deter people from taking up the habit. Tobacco use causes about 5 million deaths a year world-wide, and the figure stands to rise to 10 million by 2020, according to the US Centers for Disease Control and Prevention.

“This research adds to the wealth of evidence which shows that smoking is not good for one’s health,” said Yolanda Helfrich, an assistant professor of dermatology at the university and an author of the study. “As this evidence continues to accumulate, we can only hope that teenagers will start to pay attention,” Helfrich said in an e-mail.

In the US, smoking is responsible for one in five deaths and costs $75.5 billion annually in health-care expenses, according to the Atlanta-based CDC. The new study appears in the March issue of the Archives of Dermatology, published by the American Medical Association.

For the study, the researchers analysed the photographs and ranked skin damage on a numerical scale, with zero representing no fine wrinkling and eight representing severe fine wrinkling.

“Our observations don’t allow us to estimate how much faster skin ages for smokers relative to non-smokers,” Helfrich said. “However, we did demonstrate a significant difference in the degree of skin aging in the skin of smokers versus that of non-smokers after the age of 45.”

Smokers aged 45 to 65 had a mean wrinkling score of 2.1, while non-smokers had a score of 0.92. In those subjects over age 65, smokers had a mean wrinkling score of 6, as compared with 4.2 in non-smokers.

Previous studies linked tobacco use with the generation of harmful compounds, known as reactive oxygen species, that can damage important cellular components such as cell walls, lipid membranes and DNA, and are associated with skin ageing.

“Smokers presumably generate more reactive oxygen species, leading to a greater degree of skin ageing,” Helfrich said.